1. Technical Field
The present invention relates to the disinfection/sterilization of dental water lines and the removal of biofilm therefrom and supply of an independent source of disinfected/sterilized water for use in dental offertory applications.
2. Background Information
Tap water in dental offices is similar to drinking water in most public facilities. Although the water is generally considered safe to drink it is not sterile, but contains at least some bacteria counted by CFU/ml, (colony forming units per milliliters).
The water is transferred to the dental offertories through metal or plastic tubing and is supplied to dental handpieces and other dental implements, such as air-water syringes and ultrasonic tooth scalers. Because the water is used at a low flow rate, at infrequent intervals the internal surfaces of the supply lines are ideal for microbial contamination.
As reported by the National Center for the Chronic Disease Prevention and Health Promotion, of the Center for Disease Control, (xe2x80x9cCDCxe2x80x9d), and set forth in the report published on the Internet under the heading of xe2x80x9cWaterborne Infection Controlxe2x80x9d on Jan. 24, 2001, the problem with water with the quality of the water used in dental applications was reported more than 30 years ago. The reports states that levels of microbial contaimination as high as 10,000 to 10,000,000 CFUs/m.l. have been documented wherein the standard established by the Federal Safe Water Drinking Act for potable water is around 500 CFUs/m.l. of noncoliform bacterial.
Moreover, water that stagnates in plastic water lines and/or tubing overnight and even during long periods during the day provide bacteria the opportunity to stick to the wall of the lines/tubing. Microbial biofilm tends to form along the walls of the long, narow-bore tubing that is used to provide for cooling and irrigating water for dental hand instruments. As set forth in the aforesaid CDC report, microbial biofilm are formed by microorganisms, including bacteria, fungi, and protozoans, that colonize and replicate on the interior surfaces of the waterline tubing formaing a protective slime layer known as a xe2x80x9cglycocalyxxe2x80x9d. Due to the small diameter of the lines, the surface to volume ratio provides an excellent environment for bacterial growth. Moreover, the slow laminar flow rate of the water there through creates an area of laminar flow near the sidewalls of the tubing with very slow flowrates creating stagnant conditions.
The CDC report established that the primary source of the microorganisms is the public water supply. The American dental Association, (xe2x80x9cADAxe2x80x9d), has developed a statement on dental unit water lines acknowledging the existence of dental unit water that may be of poor microbiologic quality and has established a goal of limiting the delivery of water to dental patients during nonsurgical procedures of 200 CFUs/m or less. The panels also set forth recommended strategies of prevention including device to monitor water quality, and separate water reservoirs independent of the public water supply, purging water supplies, and inline filters. However, the report goes on to state that none of the methods known appears to permanently eradicate biofilms.
However, the instant invention provides an apparatus and method of use to eradicate dental biofilms and insure a reservoir of disinfected/sterililized water is available for dental applications in an office or laboratory setting, and even as a portable unit for remote locations.
Most dental unit water lines harbor biofilms that continually shed planktonic organisms as the water is utilized. Many different approaches are being studied to control microbial contamination. Ozone applications to dental unit water line disinfection has been limited. The major drawback appears to be the relative short half-life of ozone, which results in a lack of residual ozone in the water following treatment. The present invention provides a treatment system that reticulates ozonated water through the entire dental unit water line during a cleaning cycle to disinfect/sterilize the lines and provide a source of disinfected/sterilized water to fill a reservoir for use in dental applications in daily operations.
The present invention utilizes an apparatus for disinfecting water to make it virtually microbe-free and maintaining it in a continuous microbe-free condition for use at a center for dental instruments and the other apparatus by ozonated water. Water is ozonated and provided for disinfecting water lines and a variety of dental instruments such as drills, syringes and an expectoration bowl. At least one water reservoir is connected through fluid conduits with such instruments. An ozone producing device is connected with the water reservoir. The ozone level in reservoir or tank is replenished with fresh ozonated water periodically, usually every 24 hours. The freshly ozonated water is utilized to purify the lines and instruments. The remainder of the ozonated water remaining in the reservoir is used throughout the day for dental applications and with dental instruments.
More particularly, in the present invention, an ozone generator provides an outflow of ozone enriched air that is introduced to a water source through a venturi or optionally an ozone air pump or sparger or the like to entrain the ozone enriched air in the water. The ozonated water is conveyed through water lines to each of the various handpieces or water flow dependent implements used by a dentist during the normal course of providing dental services. The ozone introduced into the water will destroy any microbial pathogens in the water and render it essentially microbe free. Furthermore, the living organisms in any biofilm attendant the walls of the water lines will be destroyed upon contact with the ozone. Thus, the water delivered to a patient""s oral cavity during the rendering of dental services will be essentially free of any viable microbial activity.
An apparatus for generating ozone and injecting ozone into water and circulating the ozone containing water through dental water lines in a cleaning mode, and providing a source of disinfected/sterlized water for dental applications in an opeation mode includes a reservoir containing water; an ozone generator for for producing ozone; means such as an injector for injecting ozone into the water forming ozonated water; means for pressurizing the reservoir such as with air pressure from a compressor or tank or water pressure such as a city water line; means for depressuring the reservoir such as a relief valve; a pump for recirculating the water from the reservoir through the ozone generator ozonating the water forming ozonate water; an electrical power supply for the ozone generator and the pump recirculating the water; at least one line for circulating the ozonated water to at least one dental offeratory wherein a portion of the ozonated water is used in a dental application and a portion is recirculating to the reservoir; and means such as a timer, rheostat, recorder, and calorimeter for controling the activation of said ozone generator and the amount generated or bacterial content of the water for determining the selected operating intervals and cycle times.
One method method of generating and injecting ozone into water and circulating the ozonated water through dental water lines in a cleaning mode, and providing a source of disinfected/sterlized water for dental applications in an operation mode is as follows:. A cleaning mode comprises the steps of filling a reservoir containing water and opening a pressure relief valve in fluid communication with the reservoir depressurizing the reservoir; activating a power source and an ozone generator producing ozone; activating a pump circulating the water from the reservoir in fluid communication with the ozone generator through an injector in fluid communication with the ozone generator and the reservoir injecting ozone into the water forming ozonated water; and circulating the ozonated water from the reservoir through a water line in fluid communication with at least one dental offeratory for a selected period of time disinfecting/sterilizing the water line and the at least one dental offeatory, and returning the ozonated water from the offeratory to the reservoir in fluid communication with the ozonated water. The same apparatus is used in an operating mode which comprises the steps of deactivating the ozone generator and stopping circulation of the ozonated water for a selected period of time; closing the pressure relief valve in fluid communication with the reservoir for pressurizing same; pressurizing the reservoir and the water line in fluid communication therewith with pressurized air or pressurized water; storing the ozonated water in the reservoir for a selected period of time under pressure providing disinfected/sterilized water in the reservoir and the water lines in fluid communication therewith for use in dental applications.
It is therefore a primary object of the present invention to provide apparatus for delivering water from dental water lines free of any living microbes.
Another object of the present invention is to provide apparatus for destroying any biofilms formed on the walls of water lines.
Yet another object of the present invention is to provide apparatus that delivers to a dental patient water free of microbial activity whether such water be from a municipal water system or a water container.
Still another object of the present invention is to provide apparatus for destroying any microbes present in a dental water line or the water itself each time water flows through the line.
A further object of the present invention is to provide ozonated water to dental handpieces and other dental implements.
A yet further object of the present invention is to provide inexpensive apparatus for ensuring that water delivered to a dental patient is free of living microbes.
A still further object of the present invention is to provide a method for inexpensively and effectively treating and purifying water delivered to dental handpieces.
These and other objects of the present invention will become apparent to those skilled in the art as the claimed invention is described hereafter.